Tape controlled telegraph transmitter



Jan. 24, F. G, CREED ET AL TAPE CONTROLLED TELEGRAPH TRANSMITTER Filed Dec. 23. 1930 F/aZ VENTOR FREDERICK GEORGE CREED BQEGIN LD DENNIS SALMON Patented Jan. 24, 1933 UNITED STATES PATENT OFFICE rEEnEmckcEoRsE GREED AND REGINALD nENNrs SALMON, or cnoYnoN, ENGLAND, ASSIGNORS T0 OREED AND ooMrANY, LIMITED, or cRoYnoN, SURREY, ENGLAND TAPE CONTROLLED TELEGRAPH TRANSMITTER Application filed December 23, 1930, Serial No. 504,256, and in Great Britain February 12, 1930.

This invention relates to telegraph transmitters in which a perforated tape is utilized to control the movements of a contact lever, and more particularly to telegraph transmitters of this class in which small light fingers, hereinafter referred to as peckers, are arranged to co operate with signal perforations in the tape to control signalling contact means in accordance therewith.

( In telegraph transmitters of this type the peckers may be of trailing form in which after entry into a perforation the edge of the perforation itself moves the pecker away by moving against the inclined trailing tip, but a more usual arrangement is to move the pecker positively in one direction away from the perforated tape by means such as a cam or eccentric geared to the means which moves the tape. The cam or eccentric then permits the pecker to rise under spring action and this movement is permitted by a perforation, or obstructed by blank tape at this point. In such cases a signalling contact lever is maintained on one contact screw if blank tape is encountered but if a perforation occurs the contact lever is actuated over to another contact screw. By this means, signals are sent to line in accordance with the position of perforations in a tape.

Many arrangements of signalling means of this kind are known as adapted to suit different codes and methods of signalling, either one or a number of peckers may co-operate with one or a number of series of perforations in a tape to actuate a corresponding'contact lever or series of such levers; Alternatively a number of peckers may actuate a single contact lever or a number of such levers less in number than the peckers.

In telegraph transmitters of this class, the force available to actuate the contactlever by the direct action of the pecker is relatively feeble, as the spring tension or equivalent force which may beapplied to the pecker so as to enable it to enter a perforation, but yet not to pierce or unduly strain the tape if a blank portion intervenes, is very limited. Arrangements have therefore been devised whereby the movements of the peckersare caused to efl'ect a selecting movement only,

the actual operation of moving the contact lever being performed by mechanical power. At high signalling speeds of these known arrangements, however, considerable bounce of the contact lever on the contact screws takes place at each actuation and increases the apparent transit time of the contact lever.

According to the present invention a tele graph transmitter in which peckers co-operate with signal perforations in a tape to con trol the movements of signalling contact means, is characterized in that the peckers control the rotation of a mechanically driven member which member effects the movement of the signalling contact means. A transmitter according to the present invention can therefore be considered to incorporate an arrangement sometimes referred to as a mechanical relay.

The term mechanical relay in this connection may be understood to include all those forms of mechanism in which alternating and intermittent movements of a control member are utilized to control the escapement or detent of a clutch of which the driving member is rotated by mechanical power, and in which an eccentric, cam or the like on the driven member of said clutch effects movement of a second member under the control of the said control member. The chief advantage of the incorporation of an arrangement of the type in the present invention may be said to reside in the nature of the force which maintains the contact means in the position to which it has been actuated, thus opposing any tendency to bounce, in ad dition to effecting the actual movements of the signalling contact means by mechanical power. The eccentric or cam on the intermittently rotatable driven member of the clutch permits less tendency to bounce of the movable contact means. A

The clutch in a mechanical relay of this description may conveniently be formed as a plainfriction clutch of which the driven member is arrested by an escapement or de tent engaging a tooth formed thereon, but for the purposes of the present invention the preferred form of mechanical relay is that shown and claimed in our co-pending application No. 484,074, now Patent No. 1,855,- 204, granted April 26, 1932. In this case the thrusts resulting from the load are utilized to increase the frictional contact of the driving surfaces of a friction clutch. This renders the action more positive and for a given load permits a great reduction in the, dimensions and mass of the moving parts, which renders the arrangement very applicable to high speed operation under the control of smallforces as in the present invention.

It will be understood, however, that the invention is not limited to this particular form ofmechanical relay nor to the particular telegraph transmitters hereinafter described. The invention will be seen to be applicable to all types of telegraph transmittors in which signalling contact means is actuated in accordance with signal perforations 24; in a tape.

In the accompanying drawing, Figure 1 represents diagrammatically by way of e xample a transmitter according to the present inventionadapted for operation under control of a tape perforated according to the Morse land .line code whilst Figure 2 represents diagrammatically the application of the i 7 speed.

invention to a five-unitcode transmitter.

Referring to Figure 1, a shaft 1 driven by j alternately depress the two'peckers 4 and 5 through bell-crank arms 6 and 7. The peck; ers-4 and 5 are arranged to rise alternately under the tension of springs 8 and 9. against the paper tape as cams 2 and 3 rotate. When thepecker rises through a perforation inthe tape, a corresponding bell crank lever 10 or 11, rotates a sufficient angle about its corre sponding pivot 12 or 18 for a detent formed at the extremity of the upright arm of eachv bell crank, to release tooth 14of the driven member of a friction clutch, the driving member of which is shown as shaft 1. The driven member of-the clutch which carries tooth 14 and eccentric 15 has a cylindrical surface rotatably fitting in a sleeve-like extension of a driving shaft as shown and described in detailin the co-pending application Serial No. 484,074 hereinabove referred to. The two detents formed at the extremities of the said upright arms of bell crank levers 10 and 11 pecker isim eded.

andcontactlever 16 willmake contact alternately with contacts 17 and 18. As soon as a pecker encounters blank tape the correspond- 7 ing detent on u right arm or levers 10am) 11, is maintain in a position to arrest tooth 14, and contact lever,l6 is maintained to one side or the other according to whichever Figure 2's ows the manner in which a set of cyclic cams 20-24- acting directly on the pecker levers 267-30. operates a single lever 32 controlling, signalling contact means. in a manner under control of atape perforated according to a five unit code.

. In the present invention lever 32 instead of forming a contactlever, as in the known arrangements forms the escapement release of a mechanical relay. It is only necessary in this case to rotate the driving'memberof the clutch of the mechanical relay at a speed whichis not less than the signalling; impulse It isthought that. the application to an i other form of telegraph transmitter in whic 1 a contact lever is to be actuated inaccordance;

with the perforations in a tape will now be readily comprehended.

, What isclaimedis: g

1. A-tape controlledtelegraph transmitter havingm combination, a peckerco-operable with a perforated tape, a rotatable driving member, a rotatable member driven thereby, a detent holding the driven member; against rotation and actuatedaccording to the movements of said pecker to release the driven member for rotation, and signal contact meanszactuated by said driven member inv accordance with the movementsof said. pecker. 2. tape controlled telegraphtransmitter comprlslng pecker means, co-operable with signal perforations in a tape, .detentimeans actuated by said peckers, a continuously rotatable-driving member, a. driven member controlled by said detent means, and signal contact means actuated: from one; position-to another ateach movement of said driven member. 3. A tape controlled telegraphtransmitter comprising; pecker means co-operable with signal perforations in a tape, meansto feedtape, meanstopermitsaid peckers to rise into operative relation with successive'portions of said tape, detent meansactuated by said pecker; means on entry. into a, perforation, a

continuously rotatabledriving member, a

driven member released for rotationof apredetermined amount on actuation of said. detentmeans, and signal contact means actuated by said drivenmember. v I

4. In a tape controlled telegraph transmitter, pecker means co-operable with signal perforations in a tape, detent means controlled thereby, a continuously rotatable member having a concentric frictional driving surface, a driven member controlled by said detent means and having a corresponding concentric frictional surface engaging with said driving member, an eccentric on said driven member, and signal contact means actuated therefrom.

5. In a telegraph transmitter adapted to operate under control of a tape perforated according to the Morse land line code, two independent peckers operable respectively with different series of signal perforations in a tape, two corresponding detents controlled by said peckers, a rotatable member having a tooth engageable alternately with one and the other of said detents at each half revolution driving rotation and signal contact means actuated from one position to another at each half revolution of said rotatable member.

6. In a telegraph transmitter adapted to operate under control of a tape perforated according to a five unit code, a series of five independent peckers each co-operable with one of a series of corresponding signal perforations in a tape, means to bring said peckers sequentially into operative relation with said series of signal perforations, a single escapement member, actuated by any said pecker, a rotatable member controlled by said escapement, and signal contact means actuated thereby from one position to another.

7. A tape controlled telegraph transmitter having in combination, a pecker co-operable with a perforated tape, a rotatable driving member, a rotatable member to be driven thereby when coupled thereto, a detent actuated accordin to the movements of said pecker to couple and decouple the driving and driven members, and signal contact means actuated by said driven member in accordance with the movements of said pecker. In witness whereof we hereunto subscribe our names this third day of December 1930.

FREDERICK GEORGE GREED. REGINALD DENNIS SALMON. 

